Gmail's Quick Action Button for YouTube Messages

A few weeks ago, Gmail started to show a small button next to some email messages from YouTube. Click the "view video" button and you can watch the video in a new tab without even reading the message. This is one of the first built-in Gmail actions.

This only works for notifications received when a YouTube channel uploads a new video. If you visit this page when you're signed in, you can check "Email me about new uploads" next to your favorite channels.

{ Thanks, Yu-Hsuan Lin. }